Gardner Denver EFD-25 HP, Operating And Service Manual

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13--8--625 Page 41
SYMPTOM POSSIBLE CAUSE REMEDY
Compressor starts too slowly 1. Wye Delta switch time set 1. Contact your Gardner Denver
too long. distributor.
2. Minimum Pressure/Check 2. Repair or replace.
Valve is faulty.
3. Supply voltage is too low. 3. Check the supply voltage.
Compressor runs unloaded 1. Volume of compressed air 1. Check the volume of the
too often system too small. piping and air receivers.
An additional air receiver
may be required.
2. Pressure range too narrow. 2. Extend pressure range
Compressor is low on 1. Restricted air filter. 1. Clean or replace filter.
delivery and pressure
2. Sticking inlet valve. 2. Inspect and clean inlet
valve.
3. Minimum pressure valve 3. Replace valve.
stuck closed.
4. Oil separator clogged. 4. Replace
5. Intervals of moisture separator 5. Check the setting in the
drainage incorrectly set. Air Pilot controller
6. Condensate drain solenoid 6. Replace.
valve is faulty.
7. Leaks in the compressed 7. Check for leaks, fix any
air system. leaks found.
8. V--Belts broken. 8. Replace.
9. V--Belts slipping. 9. Test belt tensioning.
10. Pressure limits incorrectly 10. Check/correct pressure
set. limits in the Air Pilot Controller.
11. Aftercooler is frozen. 11. Thaw out. This machine
cannot operate in temper--
ature below 32
_ F (0 _ C).
High discharge air 1. Thermostatic mixing 1. Repair or replace valve.
temperature valve stuck open (in bypass).
2. Dirty or clogged cooler face. 2. Clean cooler.
3. Insufficient cooling 3. Provide unrestricted supply
air flow. of cooling air.
4. Clogged oil filter or 4. Replace filter or clean
cooler (interior). cooler.
5. Low compressor oil. 5. Add oil to proper level.
6. Faulty temperature sensor. 6. Repair sensor.